<?php
/**
 * Unified diff generator for PHP DiffLib.
 *
 * PHP version 5
 *
 * Copyright (c) 2009 Chris Boulton <chris.boulton@interspire.com>
 * 
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 *
 *  - Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *  - Neither the name of the Chris Boulton nor the names of its contributors 
 *    may be used to endorse or promote products derived from this software 
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * @package DiffLib
 * @author Chris Boulton <chris.boulton@interspire.com>
 * @copyright (c) 2009 Chris Boulton
 * @license New BSD License http://www.opensource.org/licenses/bsd-license.php
 * @version 1.1
 * @link http://github.com/chrisboulton/php-diff
 */
require_once dirname ( __FILE__ ) . '/../Abstract.php';
class Diff_Renderer_Text_Unified extends Diff_Renderer_Abstract {
	/**
	 * Render and return a unified diff.
	 *
	 * @return string The unified diff.
	 */
	public function render() {
		$diff = '';
		$opCodes = $this->diff->getGroupedOpcodes ();
		foreach ( $opCodes as $group ) {
			$lastItem = count ( $group ) - 1;
			$i1 = $group [0] [1];
			$i2 = $group [$lastItem] [2];
			$j1 = $group [0] [3];
			$j2 = $group [$lastItem] [4];
			
			if ($i1 == 0 && $i2 == 0) {
				$i1 = - 1;
				$i2 = - 1;
			}
			
			$diff .= '@@ -' . ($i1 + 1) . ',' . ($i2 - $i1) . ' +' . ($j1 + 1) . ',' . ($j2 - $j1) . " @@\n";
			foreach ( $group as $code ) {
				list ( $tag, $i1, $i2, $j1, $j2 ) = $code;
				if ($tag == 'equal') {
					$diff .= ' ' . implode ( "\n ", $this->diff->GetA ( $i1, $i2 ) ) . "\n";
				} else {
					if ($tag == 'replace' || $tag == 'delete') {
						$diff .= '-' . implode ( "\n-", $this->diff->GetA ( $i1, $i2 ) ) . "\n";
					}
					
					if ($tag == 'replace' || $tag == 'insert') {
						$diff .= '+' . implode ( "\n+", $this->diff->GetB ( $j1, $j2 ) ) . "\n";
					}
				}
			}
		}
		return $diff;
	}
}